The present invention relates to a system for distributing liquid, and in particular, to a system for distributing liquid to a damper in a gas turbine engine.
Gas turbine engines typically have shafts for fans and spools that rotate at high speed during operation. Small imbalances associated with the rotating shafts can cause these shafts to vibrate in a radial direction with respect to a centerline axis of the shaft. Such vibrating motion is commonly referred to as synchronous vibration or whirl of the shaft. Amplitude of the vibration can become relatively large as the frequency approaches or passes through a resonant frequency of the overall system. These shafts are typically supported by bearings, which, tend to be relatively stiff and transmit vibration to the engine. In order to reduce engine damage as a result of this vibration, one or more of the bearings are often supported by a damper such as a thin fluid film vibration damper. These dampers damp the vibration amplitude and can also shift the resonant frequency of the system.
Thin fluid film vibration dampers use a thin film of liquid positioned between two closely spaced surfaces to achieve the damping effect. Typical gas turbine engines supply this liquid with a main lubricating liquid pump. The main lubricating liquid pump is usually driven off the high pressure spool and positioned toward the aft of the engine. In order to supply liquid to a damper near the front of the engine, a relatively large amount of external piping is used to span the distance. That piping can take up space and add undesired weight to the engine.